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. 2015 May 29;1(4):e1400254. doi: 10.1126/sciadv.1400254

Fig. 5. Distributions of horizontal and vertical disparities.

Fig. 5

(A) Joint distributions of horizontal and vertical disparities in different regions of the visual field. The black circle in the background represents the central 20° of the visual field (10° radius) with the fovea at the center. Each subplot shows the joint disparity distribution in a different region of the visual field. Horizontal disparity is plotted on the abscissa of each subplot and vertical disparity on the ordinate. The scales for the abscissa and ordinates differ by a factor of 10, the abscissa ranging from −0.5° to +0.5° and the ordinate from −0.05° to +0.05°. The centers of the represented regions are either at the fovea or 4° from the fovea. The regions are all 3° in diameter. Frequency of occurrence is represented by color, darker corresponding to more frequent disparities. The curves at the top and right of each subplot are the marginal distributions. Horizontal and vertical disparities are positively correlated in the upper left and lower right parts of the visual field and negatively correlated in the upper right and lower left parts of the field (absolute r values greater than 0.16, P values less than 0.001). One can see in these panels the shift from uncrossed (positive) horizontal disparity in the upper visual field to crossed (negative) disparity in the lower field. We calculated the range of horizontal disparities needed to encompass two-thirds of the observations in each of the nonfoveal positions in the figure. For the upper middle, upper right, mid right, lower right, lower middle, lower left, mid left, and upper left regions, the disparity ranges were respectively 0.69°, 1.37°, 0.53°, 0.73°, 0.49°, 0.72°, 0.25°, and 0.43°; the average across regions was 0.74°. (B) Joint distribution of horizontal and vertical disparities in the central 20° (10° radius) of the visual field. The format is the same as the plots in A. Movies S1 and S2 show how the marginal distribution of horizontal disparity changes as a function of elevation and azimuth.